Disabled Rider Trying to Make His Ride Easier

[Chelagroove]

Ok so this is a bit different... I own an adapted trike and it has a 750w bafang motor and an Alfine 11 hub with Di2 shifting. I have just added a second battery with the dateX2 to get long range for off road/gravel large days out.
I have my old iPhone XS connected so I can see which gear I'm in and Bafang DP18 C display. Now the main issue I have is that my hands need to be tied to the hand cranks as I'm paralysed and though I can do most terrain in assist mode 3 of 9 I can't get up the biggest hills without increasing PAS to 5+

As my hands are tied to the pedals can anyone suggest a way to do this with voice control or Bluetooth switches or wired switches to say mouth switch

 

[matthewslack]

I don't know any of those parts first hand, but it looks like the Bafang display has a separate switch unit. The first question is whether these are simple switches directly connected via the cable to the display, or whether there is a communication protocol at work there. I can't answer that.

If simple switches, then replacing or parallel connecting more suitable switches would sort it out.

If it is a communication protocol, then one approach is to open up the switch unit and replace the physical switches with the same more suitable switches.

'More suitable switches' can make use of standard microprocessor based diy solutions from the 'maker' world.

 

[saneagle]

It would be easier to attach a throttle connector and switch, which would override the pedal assist setting. All you need is a simple switch to give the 4v or whatever level you want using a voltage divider between the ground and the 5v. The switch could be attached to a lever located somewhere that some moving part of your body can reach. 4v on the throttle signal wire would give instant maximum power while you held the switch on.

 

[thelarkbox]

Does your display phone connection support remote control of the bike?
If not hacking into the wire between buttons and display would be easy enough.
A pressure switch or sensor attached to a tube for sucking/blowing might be an option for 'pressing up' or 'pressing down' and if a sensor - arduino is probably the best platform for the control with the widest support and active forums to help, but if you have any programming experience its simply a case of a quick edit of the example program supplied for any suitable sensor.

**EDIT google tells me this is known as 'sipp and puff' control and surprise surprise its been done and documented..

 

[matthewslack]

Just remember to include the equivalent of brake sensors, whatever you do, so that in an awkward or emergency situation you can always safely stop.

 

[Woosh]

I suggest you look into an arduino project with bluetooth to create a wireless/remote switch system. The switch part is then connected to the + and - buttons and the control part has two buttons and is located in the hollow of one of the pedals.

 

[thelarkbox]

Arduino Controlled SIP & PUFF Switch

Arduino Controlled SIP & PUFF Switch: The Arduino series of micro-controllers opens up a huge world of possibilities for novice programmers and hobbyists! With freely available development systems and tutorials, and a vast array of library functions and sample sketches, just about anyon…

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[AntonyC]

It's reported the Alfine 11 isn't all that robust with mid-drives. I'd use saneagle's method but add a capacitor to ramp up the torque until it's just enough, as set by a trim pot, and of course brake sensors.

Can you give us an idea of what you can operate most easily and whether you'd find a button or switch away from the hand cranks practical, for simplicity?

 

[Chelagroove]

Thanks everyone for your replies so far. In terms of body function to hit a switch to temporarily boost speed does sound like the best option. Something that I can hit on or off or lean on. Like a spring where you let go it releases back. As my hands are tied onthere is definitely no easy access. The sip and puff method might work but complicates things with routing- might start with Saneagle's suggestion- the Alfine 11 i'm using is eBike rated and more up-to-date, I do also have a rolloff hub, but that doesn't have an aftermarket electronic shifting solution at the moment. I can buy the E14 off eBay but I'm not sure about integrating that into the Bafang. It would definitely be my preference in terms of gear, ranging and reliability.

 

[guerney]

Disabled Rider Trying to Make His Ride Easier

To make your ride easier, why not keep things simple and use the highest level of assist at all times, and use a larger battery? I myself hardly ever use any level other than the highest on my BBS01B. The only time I use a lower level, is when I'm running extremely low on battery. My 19.2Ah battery ensures there's no range anxiety under 43 miles.

With a 750W BBS02, you could use one gear. No shifting required. Because I don't have a throttle on my bike, if I am stopped on my highest gear unexpectedly, I can just about activate the cadence sensing pedal assist on my 20" wheeled bike, by standing on the pedals. Of course you won't be able to exert a similar force using your arms, but you could determine the highest gear it's possible for you to start pedal assistance with, and never shift from that? On flat ground, once pedal assistance is activated on my highest gear, even my 36V X 15A = 540W BBS01B motor is capable of accelerating my bike to 15.5mph. Once the BBS02's 48V X 25A = 1200W pedal assistance starts, the motor is well capable of doing the rest. With that much power, you could probably climb most tarmaced hills with one gear - determine which gear allows standing starts and hill climbs with 1200W?

"Start degree" set to 4, works well for me. Set "Keep current" to 100%.

Bafang Programming - Learn how to improve your Bafang mid-drive ebike - Edrivenet

Learn how to improve your Bafang mid-drive ebike. Reprogramming your Bafang mid-drive system can improve the usability and performance of your ebike a lot.

edrivenet.com

 

[AntonyC]

It can feel nicer to have more control than constant full assist. As touch points are 'arcade button', 'long sprung toggle switch' and 'lever microswitch' in a neoprene cover on the right lines? They can be leant on bodily, equally you could have them on a pedal with bluetooth or a flying cable.

The big advantage to matthewslack's approach is not needing brake sensors or a shift interlock. With a centre sprung toggle on a cable you'd have two direct outputs and most likely not need an Arduino, BT receiver, power, waterproof housing etc.

 

[guerney]

It can feel nicer to have more control than constant full assist.

It feels horrible not having constant full assist, owing to my impact damaged right knee. As for control: with "Start current" at 10%, although pedal assistance activation is fast, power delivery increases with no jerky/joltiness, and pedal assistance stops rapidly.

The OP could experiment with a single gear setup, the only purchase being a programming cable. It'd better be a robust gear.

 

[AntonyC]

Another option might be to extend the DP18C remote's lead and enlarge the original +/- buttons using hinged plastic tabs.

 

[guerney]

Another option might be to extend the DP18C remote's lead and enlarge the original +/- buttons using hinged plastic tabs.

A couple of waterproof blister buttons glued to the back of a gumshield, for tongue push activation?

 

[Chelagroove]

To make your ride easier, why not keep things simple and use the highest level of assist at all times, and use a larger battery? I myself hardly ever use any level other than the highest on my BBS01B. The only time I use a lower level, is when I'm running extremely low on battery. My 19.2Ah battery ensures there's no range anxiety under 43 miles.

With a 750W BBS02, you could use one gear. No shifting required. Because I don't have a throttle on my bike, if I am stopped on my highest gear unexpectedly, I can just about activate the cadence sensing pedal assist on my 20" wheeled bike, by standing on the pedals. Of course you won't be able to exert a similar force using your arms, but you could determine the highest gear it's possible for you to start pedal assistance with, and never shift from that? On flat ground, once pedal assistance is activated on my highest gear, even my 36V X 15A = 540W BBS01B motor is capable of accelerating my bike to 15.5mph. Once the BBS02's 48V X 25A = 1200W pedal assistance starts, the motor is well capable of doing the rest. With that much power, you could probably climb most tarmaced hills with one gear - determine which gear allows standing starts and hill climbs with 1200W?

"Start degree" set to 4, works well for me. Set "Keep current" to 100%.

Bafang Programming - Learn how to improve your Bafang mid-drive ebike - Edrivenet

Learn how to improve your Bafang mid-drive ebike. Reprogramming your Bafang mid-drive system can improve the usability and performance of your ebike a lot.

edrivenet.com

I did this before, however, it’s my only cardio for one, and only just, being a tetraplegic I can only use my arms. I also am a keen mountain biker and want to come close to a real riding experience, lastly the trike weighs probably 40kg.

 

[guerney]

Another option might be to extend the DP18C remote's lead and enlarge the original +/- buttons using hinged plastic tabs.

Or a couple of bite-restistant switches situated on a horizontal rod? Lean forward, bite up/down. I hesitate proclaiming The GuerneyBiteYourPAS™®©℠ invented.

 

[guerney]

I don't know any of those parts first hand, but it looks like the Bafang display has a separate switch unit. The first question is whether these are simple switches directly connected via the cable to the display, or whether there is a communication protocol at work there. I can't answer that.

They're basic swiches, on the 850C at least. Highly likely similar for the DPC-18 - there's no CAN bus, but there is on the DPC181.

How do you unlock a Bafang e-bike display when you have forgotten the secuirty pin?

If you find this article useful and you would like to support the work we do as an All Ability Cycling charity please consider sending us a small domain via our PayPal Charity fund page. So I wante…

empoweredpeople.co.uk

 

[guerney]

I did this before, however, it’s my only cardio for one, and only just, being a tetraplegic I can only use my arms. I also am a keen mountain biker and want to come close to a real riding experience, lastly the trike weighs probably 40kg.

That's a heavy trike, stating the obvious there.

Would you be able to lean forward and operate the level up/down buttons with your nose, if you somehow situated the button pad below the display? Glue/superglue+baking soda/epoxy the two of them together to a piece of plastic/wood/aluminium behind the display and buttons? Or secure the button pad onto a Minoura space mount or similar?




These can be oriented horizontally or vertically, available in different sizes.

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If you need extra cockpit space for lights or computers, the new Minoura SG 400 Space Grips are now sleeker and more secure than ever. Now with a stronger clamping mechanism that can stay attached to the bike, the Space Grip SG400 also has a sleek finish that enhances your handlebar space. Space...

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[matthewslack]

That's an impressive machine!

Do you have the ability to squeeze your hand cranks together, and/or pull them apart, or any wrist movement to rotate one relative to the other?

The switches are technically simple, just need to find the movement that you can most easily make, and then find a way to capture it.

 

[matthewslack]

Alternatively is there any mileage in mapping your Alfine gear selection to a motor setting?